Folding or drop-leaf tables are well-known in the art, for example, as shown in U.S. Pat. No. 1,840,249 to Palumbo. Hinges mounted between a center portion and a side leaf of the table allow a 90 degree pivoting movement of the leaf from the horizontal to the downward position so that the table can be used or stored in a smaller space. Some folding tables have the center portion pivotably mounted on an open base so that the table can be pivoted to a vertical position and stacked or nested in parallel with other tables.
A further development in folding tables has been the use of three-position hinges to also allow the leaf to be pivoted to an upward position, so that the table has a smaller profile and the leaf keeps objects placed on the table from falling off when the table is moved or wheeled about. However, conventional three-position hinges generally extend outwardly from the edge of the center portion in order to provide the folding leaf clearance for 180 degrees of movement through the three positions. This construction has the disadvantage of an unsightly appearance due to the edge of the leaf becoming spaced from the edge of the center portion by a wide gap when it is pivoted to the downward or upward positions.
Concealed hinges are well-known in the art, for example, as shown in U.S. Pat. Nos. 1,114,026 to parsons, 1,326,305 to Tammi, 1,502,431 to Hubbard, or 2,215,088 to Soss. However, such concealed hinges are generally of the two-position type having only 90 degrees of pivoting movement, and are not suitable for three-position movement.
Accordingly, it is a principal object of the invention to provide a three-position hinge which allows a movable member to pivot through 180 degrees of movement relative to a stationary member while keeping the edges of the members close together so that no unsightly gap is created therebetween at any of the three positions. A further object is to provide a folding table which utilizes three-position hinges to allow the leaf to be moved between a stable upward position, closely spaced horizontal position, and a vertical lower position.